Drowning is a leading cause of unintentional injury death among children in the United States. Children under the age of five years are at particularly increased risk with drowning rates peaking among 1-2 year olds. While some preventive strategies, such as pool fencing, are known to be effective, the impact of other preventive strategies is unclear. For example, data regarding the relationship between swimming lessons or swimming ability and the risk of drowning are lacking, making it difficult to formulate guidelines and policies about enrollment of young children in swimming lessons. Information about risk and protective factors for childhood drownings will provide valuable guidance for the design of future interventions to prevent these tragic deaths. This study utilizes a case-control design to evaluate the relationship between swimming lessons, swimming ability, and other risk or protective factors on the one hand, and the risk of drowning on the other. The primary study hypothesis addresses the relationship between swimming lessons and the risk of drowning among children ages 1 to 4 years, while secondary hypotheses address risk and protective factors for drowning among older children. Parents or guardians of drowning victims and parents/guardians of age-matched controls will be interviewed. A short interview will also be conducted with adolescent controls, aged 14-19 years. Interviews include questions regarding exposure to water, swimming ability, participation in swimming lessons, and a number of other factors that might influence the risk of drowning. Data collection for this study began in April, 2003 and is expected to continue through September, 2005.